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1.
Statistical applications of linear assignment   总被引:1,自引:0,他引:1  
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2.
This paper discusses rowwise matrix correlation, based on the weighted sum of correlations between all pairs of corresponding rows of two proximity matrices, which may both be square (symmetric or asymmetric) or rectangular. Using the correlation coefficients usually associated with Pearson, Spearman, and Kendall, three different rowwise test statistics and their normalized coefficients are discussed, and subsequently compared with their nonrowwise alternatives like Mantel'sZ. It is shown that the rowwise matrix correlation coefficient between two matricesX andY is the partial correlation between the entries ofX andY controlled for the nominal variable that has the row objects as categories. Given this fact, partial rowwise correlations (as well as multiple regression extensions in the case of Pearson's approach) can be easily developed.The author wishes to thank the Editor, two referees, Jan van Hooff, and Ruud Derix for their useful comments, and E. J. Dietz for a copy of the algorithm of the Mantel permutation test.  相似文献   

3.
探讨消费欲望的影响因素及影响机制对解决个体非健康饮食问题具有重要意义。采用2个实验考察感知食物空间距离是否及如何影响消费欲望,以及感知资源口腔占用是否会降低感知空间距离对消费欲望的影响。结果发现:(1)感知空间距离越近,消费欲望越强;(2)感知空间距离通过心理模拟影响消费欲望;(3)占用感知资源口腔会阻碍心理模拟从而降低感知食物空间距离对消费欲望的影响。因此,操纵食物的感知空间距离会通过心理模拟影响个体的消费欲望。  相似文献   

4.
Correspondence analysis and optimal structural representations   总被引:1,自引:0,他引:1  
Many well-known measures for the comparison of distinct partitions of the same set ofn objects are based on the structure of class overlap presented in the form of a contingency table (e.g., Pearson's chi-square statistic, Rand's measure, or Goodman-Kruskal'sτ b ), but they all can be rephrased through the use of a simple cross-product index defined between the corresponding entries from twon ×n proximity matrices that provide particular a priori (numerical) codings of the within- and between-class relationships for each of the partitions. We consider the task of optimally constructing the proximity matrices characterizing the partitions (under suitable restriction) so as to maximize the cross-product measure, or equivalently, the Pearson correlation between their entries. The major result presented states that within the broad classes of matrices that are either symmetric, skew-symmetric, or completely arbitrary, optimal representations are already derivable from what is given by a simple one-dimensional correspondence analysis solution. Besides severely limiting the type of structures that might be of interest to consider for representing the proximity matrices, this result also implies that correspondence analysis beyond one dimension must always be justified from logical bases other than the optimization of a single correlational relationship between the matrices representing the two partitions.  相似文献   

5.
Based on a simple nonparametric procedure for comparing two proximity matrices, a measure of concordance is introduced that is appropriate whenK independent proximity matrices are available. In addition to the development of a general concept of concordance and specific techniques for its evaluation within and between the subsets of a partition of theK matrices, several methods are also suggested for comparing and/or for fitting a particular structure to the given data. Finally, brief indications are provided as to how the well-known notion of concordance forK rank orders can be included within the more general framework.Partial support for this research was supplied by the National Science Foundation through SOC-77-28227.  相似文献   

6.
7.
The association structure between manifest variables arising from the single-factor model is investigated using partial correlations. The additional insights to the practitioner provided by partial correlations for detecting a single-factor model are discussed. The parameter space for the partial correlations is presented, as are the patterns of signs in a matrix containing the partial correlations that are not compatible with a single-factor model.  相似文献   

8.
A permutation procedure is described for statistically comparing a given classification scheme, characterized as a hierarchically organized collection of subsets, to either a proximity matrix or a second classification scheme defined on the same basic set of objects. To prevent a bias that may result when an optimization method is used to construct the classification structures being considered, it is assumed that the desired comparisons involve classifications and/or proximities that have been derived from separate sources. In addition to an extensive number of examples used to clarify the major points in the presentation of the inference strategy, several heuristic optimization techniques are also introduced and illustrated. These latter procedures attempt to “fit” the form of a target classification structure by relabeling the rows and simultaneously the columns of a given proximity matrix to maximize the correspondence between the fixed target and the relabeled proximity matrix.  相似文献   

9.
Prins N 《Perception》2008,37(7):1022-1036
It has been suggested that correspondence matching in long-range motion is mediated by a perceptually high-level, 'intelligent' system. This suggestion is based on findings that long-range motion can be perceived between stimuli that could not be detected by lower-level motion mechanisms acting on Fourier motion energy, and that correspondence matching is affected by featural similarities between motion tokens that would be invisible to low-level (Fourier) motion detectors. Here, the effects of spatial-frequency content, color, and binocular disparity on correspondence matching are investigated. It is shown that the effects of featural matches between motion tokens develop only over time and lag behind the effects of the relative proximity between motion tokens in the retinal projection. This suggests that correspondence matching in long-range apparent motion is mediated by a mechanism which acts initially on the retinal coordinates of the motion tokens only, but may be biased to favor matching tokens that are featurally similar through a slower top-down influence by higher-level processes.  相似文献   

10.
Following up on articles recently published in this journal, the present contribution tells (some of) “the rest of the story” about the value of randomization in single‐case intervention research investigations. Invoking principles of internal, statistical‐conclusion, and external validity, we begin by emphasizing the critical distinction between design randomization and analysis randomization, along with the necessary correspondence between the two. Four different types of single‐case design‐and‐analysis randomization are then discussed. The persistent negative influence of serially dependent single‐case outcome observations is highlighted, accompanied by examples of inappropriate applications of parametric and nonparametric tests that have appeared in the literature. We conclude by presenting valid applications of single‐case randomization procedures in various single‐case intervention contexts, with specific reference to a freely available Excel‐based software package that can be accessed to incorporate the present randomization schemes into a wide variety of single‐case intervention designs and analyses.  相似文献   

11.
Psycholinguistic research faces a major challenge in describing the mental representations readers construct from a text. It is now widely accepted that readers end with a representation of the situation described in the text. However, it is unclear whether this representation allows the activation of elements in accordance with their situation proximity. To answer this question, two experiments were conducted. Participants read texts, sentence by sentence, which gave them instructions about how to arrange items in a layout; they then performed a recognition task. By manipulating the spatial proximity between prime and probe items, this task allowed the measurement of a spatial priming effect. In the first experiment, a larger priming effect was observed for closer items on the spatial layout. The second experiment replicated these findings and showed that the priming effects are better explained by categorical distance than by Euclidean distance.  相似文献   

12.
Despite broad consensus regarding the value of the impulsive/premeditated and reactive/proactive aggression classifications, confusion as a result of imprecise language and the exact nature of subtypes have threatened its utility for clinical and research purposes. In order to increase the usefulness of these subtypes in research, prevention, and treatment, the current review examines whether differences in these two subtype classifications are theoretical, semantic or empirical. Correlates of impulsive, premeditated, reactive, or proactive aggression measures were examined for consistency. Based on the different conceptual roots, we expected that each subtype pair would evidence only partial correspondence such that the classification systems may actually be capturing different constructs. The findings of a targeted and selective review suggest there is more correspondence between reactive and impulsive aggression than there is between proactive and premeditated aggression. An agenda for future research is outlined.  相似文献   

13.
Extensions of the partial credit model   总被引:1,自引:0,他引:1  
The partial credit model, developed by Masters (1982), is a unidimensional latent trait model for responses scored in two or more ordered categories. In the present paper some extensions of the model are presented. First, a marginal maximum likelihood estimation procedure is developed which allows for incomplete data and linear restrictions on both the item and the population parameters. Secondly, two statistical tests for evaluating model fit are presented: the former test has power against violation of the assumption about the ability distribution, the latter test offers the possibility of identifying specific items that do not fit the model.The authors are indepted to professor Wim van der Linden and Huub Verstralen for their helpful comments.  相似文献   

14.
The purpose of the present study was to investigate the statistical properties of two extensions of the Levin-Wampold (1999) single-case simultaneous start-point model's comparative effectiveness randomization test. The two extensions were (a) adapting the test to situations where there are more than two different intervention conditions and (b) examining the test's performance in classroom-based intervention situations, where the number of time periods (and associated outcome observations) is much smaller than in the contexts for which the test was originally developed. Various Monte Carlo sampling situations were investigated, including from one to five participant blocks per condition and differing numbers of time periods, potential intervention start points, degrees of within-phase autocorrelation, and effect sizes. For all situations, it was found that the Type I error probability of the randomization test was maintained at an acceptable level. With a few notable exceptions, respectable power was observed only in situations where the numbers of observations and potential intervention start points were relatively large, effect sizes were large, and the degree of within-phase autocorrelation was relatively low. It was concluded that the comparative effectiveness randomization test, with its desirable internal validity and statistical-conclusion validity features, is a versatile analytic tool that can be incorporated into a variety of single-case school psychology intervention research situations.  相似文献   

15.
Randomization statistics offer alternatives to many of the statistical methods commonly used in behavior analysis and the psychological sciences, more generally. These methods are more flexible than conventional parametric and nonparametric statistical techniques in that they make no assumptions about the underlying distribution of outcome variables, are relatively robust when applied to small‐n data sets, and are generally applicable to between‐groups, within‐subjects, mixed, and single‐case research designs. In the present article, we first will provide a historical overview of randomization methods. Next, we will discuss the properties of randomization statistics that may make them particularly well suited for analysis of behavior‐analytic data. We will introduce readers to the major assumptions that undergird randomization methods, as well as some practical and computational considerations for their application. Finally, we will demonstrate how randomization statistics may be calculated for mixed and single‐case research designs. Throughout, we will direct readers toward resources that they may find useful in developing randomization tests for their own data.  相似文献   

16.
A sound presented in temporal proximity to a light can alter the perceived temporal occurrence of that light (temporal ventriloquism). The authors explored whether spatial discordance between the sound and light affects this phenomenon. Participants made temporal order judgments about which of 2 lights appeared first, while they heard sounds before the 1st and after the 2nd light. Sensitivity was higher (i.e., a lower just noticeable difference) when the sound-light interval was approximately 100 ms rather than approximately 0 ms. This temporal ventriloquist effect was unaffected by whether sounds came from the same or a different position as the lights, whether the sounds were static or moved, or whether they came from the same or opposite sides of fixation. Yet, discordant sounds interfered with speeded visual discrimination. These results challenge the view that intersensory interactions in general require spatial correspondence between the stimuli.  相似文献   

17.
Two experiments examined the probed recall of visually presented letter sequences in which the items appeared at different spatial locations. Three types of probe were compared: (1) spatial position; (2) temporal association; and (3) combined position and association. In the first experiment, in which the spatial locations of the items were correlated with their temporal order, spatial probes were more effective than temporal association probes. In the second experiment spatial location was uncorrelated with temporal order, and spatial probes were less effective than temporal association probes. Regardless of the probe, errors tended to be items presented close in time to correct responses: spatial proximity was far less important. The results are discussed in terms of a storage system in which items and their spatial locations are organized within a temporal format. Both experiments showed superior combined probe performance, demonstrating that short-term retrieval is not limited to the use of one type of cue at a time. Secondary aspects of the results showed additionally that subjects can “edit” their responses to avoid making obvious mistakes, and that spatial location can be partially forgotten rather than being completely lost.  相似文献   

18.
In this paper, we prove the correspondence between complete extensions in abstract argumentation and 3-valued stable models in logic programming. This result is in line with earlier work of [6] that identified the correspondence between the grounded extension in abstract argumentation and the well-founded model in logic programming, as well as between the stable extensions in abstract argumentation and the stable models in logic programming.  相似文献   

19.
The relationship between strategy use and cognitive training gains on reasoning ability is examined in a sample of 393 older participants in the Seattle Longitudinal Training Study. Pre- and posttest gains on the use of strategies specific to reasoning ability were compared for the elderly trained on reasoning versus spatial orientation ability. The present study involves an objective behavioral method of measuring strategy use on tests of inductive reasoning. Results showed that participants trained on reasoning significantly increased strategy use from pre- to posttest on two reasoning outcome measures compared to participants trained on spatial orientation. Higher strategy use by inductive reasoning trainees was also associated with greater training gain on reasoning outcome measures, suggesting strategy use as a possible mechanism of training gain. In addition, young–old participants and those with higher education, irrespective of training condition, exhibited greater pre- to posttest gain in strategy use.  相似文献   

20.
Are spatial proximity (0.10-12.5 cm), temporal proximity (0-, 2-, and 5-s gaps), and/or perceived connectedness of stimulus and reward key to infants' ability to deduce an abstract nonmatching rule from reward feedback? In this investigation, 3 conditions of the delayed nonmatching to sample task were administered to infants 9, 12, and 15 months old, and 5 more conditions were administered just to 12-month-olds. Results showed that connectedness is key. In its presence, neither close spatial or temporal proximity was needed. In the absence of the perception that stimulus and reward were components of a single thing, even close spatial and temporal proximity were insufficient for infants in the 1st year to grasp the rule-based association between stimuli and rewards.  相似文献   

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